Research On Coordinated Brake Control Of Trailer-mounted Recreational Vehicle

With the increase in the sales of trailer-type motorhomes and the popularity of drum-type electromagnetic brakes on trailer-mounted motorhomes,how to achieve effective control of brakes has become a concern of many motorhome manufacturers.When turning the brakes,the trailer and the RV as a whole have a complicated force,which leads to frequent safety accidents.By effectively controlling the output torque of the RV electromagnetic brake to improve safety,which is the research focus of this paper.Firstly,this paper analyzes the influence of the yaw and roll motion of the trailer and the RV on the vertical load of each wheel and the side angle of the tire by establishing the differential equation of the motion of the trailer.By analyzing the structural principle of the electromagnetic brake,it is established.The theoretical model of the electromagnetic brake is used,and the relationship between the input current and the output torque is plotted using Matlab/Simulink.By establishing a nonlinear model of the tire and analyzing the mechanical properties of the tire,the specific relationship between the longitudinal braking force and the slip ratio of the tire is obtained,which provides a basis for the subsequent use of the slip rate control to obtain the required braking force.Secondly,based on CarSim simulation software,the simulation model of trailermounted RV is established,and the linear braking and steady-state braking simulation are carried out respectively.The real vehicle experiment is designed and tested to verify the reliability of the simulation model.The model is used to simulate the turning and braking instability on the road with different adhesion coefficients,and the relationship between the locking and instability types of different axles.The reasonable distribution of braking force is discussed,and the road surface adhesion coefficient is fully utilized to improve the braking safety.The method of stability.Finally,in order to obtain the reasonable braking force of the left and right brakes of the RV,this paper establishes the two-degree-of-freedom differential equation of the trailer to derive the ideal yaw rate of the trailer and the RV.Combined with the ideal longitudinal deceleration and road surface attachment conditions,the slip rate control strategy of the RV wheel is obtained,which has certain feasibility in practical applications.The simulation proves that the braking strategy can effectively reduce the braking distance and the maximum yaw rate.